Can You Recharge an EV With Solar Power?

Electric cars are the way to go as the world moves toward a more sustainable future, taking into account climate change and its effects. Solar is considered the only truly smart and sustainable energy source for charging EVs. Before we delve into the details of how to set up your home EV solar charging systems, here are more reasons why you should opt for solar instead of grid power.

Why Recharge Your EV Using Solar Power?

You should consider recharging your EV with solar power, and here are the reasons why.

1. Save on Costs

Firstly, even without using solar power, charging an EV is way cheaper than the cost of gas. A 2018 study by the Transportation Research Institute of the University of Michigan found that the average annual cost of operation for a gasoline-powered vehicle was $1,117, while for an EV it’s $485.

The prices might have gone up slightly after the pandemic, but it still shows that it is cheaper to own an EV instead of a gas car, especially in the long run. You can cut the cost further by charging your EV using solar panels. Though the initial cost of installing a solar charging system is high, once installed, you can charge your car for several years without spending a dime. 

2. Reduce Pollution

Pollution from the use of solar panels is almost insignificant compared to the pollution that results from using fossil fuel or grid power. According to the US Department of Transportation, the average American driver spends about 450 gallons of gas annually, producing about 8,800 lbs of CO2 emissions. 

An EV owner, however, spends about 3,780 kWh of power annually. Given that CO2 emissions for grid power are at 0.41 lbs/kWh, this is approximately 1,531 lbs. On the other hand, the CO2 emissions from a solar panel are at 0.088 lbs/kWh and are bound to go down as more energy-efficient panels enter the market.

Therefore, to generate 3,780 kWh of energy, home solar panels would produce only 368 lbs of CO2 emissions. While having an EV is the right step towards a more sustainable future, solar charging further reduces your carbon footprint per mile.

3. Get IRA Tax Credits

In August 2022, President Biden signed the Inflation Reduction Act. In it are several incentives for electric cars and solar panels. Topping the list is the 30% investment tax credit for buying an EV, new or used. 

If you go further and opt to use solar panels to power your home or, in this case, charge your car, you will qualify for a 30% investment tax credit (ITC) until 2033, after which it will be reduced to 26%. Additionally, for the first time, stand-alone storage systems are included in the ITC bracket!

You can get a 30% tax credit if you buy a battery to store power in when power rates are high. This is a good option when using solar power to charge your electric vehicle.

4. No Need to Worry About Time-of-Use Metering or Billing

Electricity costs vary depending on the time of the day, and they’re cheapest at night. Even then, the lowest price still varies from state to state, with some charging as low as $0.07/kWh. However, when using a solar panel to charge your EV, these are the least of your worries. 

Another issue that falls off the list of your concerns, unless you are far away from home, is the charging cost variance based on location. Tesla and Blink, for example, charge between twice to five times more.

Key Considerations When Setting up EV Solar Charging

Here are four main issues to consider when setting up or purchasing a home solar charging system for your EV. They are worth knowing to ensure you ask the right questions when discussing it with your installers.

1. EV Battery Capacity and Range

The first step is to understand the capacity of the battery powering your electric car. While the capacity indicates the amount of power it can hold, in kWh, the range shows the mileage you can get out of that power.

Understanding this is essential as it determines the required number of solar panels and how often you will need to recharge your car. According to the Electric Vehicle Database, the capacity and range of EV battery is 66.7 kWh and 3.1 miles per kWh, respectively.

However, this range varies depending on several factors, such as driving conditions and the efficiency level of the car. Generally, efficiency-centered EVs have a more extended range than performance EVs.

2. Number of Solar Panels

The easiest way to calculate this is to consider your daily mileage, assuming you will be charging the car overnight. Going by the average of 40 miles per day and a range of 3.1 miles/kWh, you will need to charge your vehicle between 13kWh to 18kWh of electricity per day. 

The modern residential solar panel produces between 250 and 400 watts every hour. Also, depending on where you live, you can get 3 to 7 hours of insolation daily. Therefore, if you opt for a 320 watts panel, you will get 0.96kWh to 2.24kWh per day from one solar panel. 

So, if you drive the Peugeot e-208, which has a range of 3.9 miles per kWh, you will need 10.25 kWh, which you can get using 5 to 8 solar panels. Undoubtedly, the number of panels increases when you drive a high-performance car. 

For example, you will need 20 to 30 320-watt panels to juice out 40 miles per day from the high-performance Mercedes EQV 300 series, as they consume about 0.4 kWh/mile. This limits their range to about 2 miles/kWh.

3. Power Inverter and Battery

The next major equipment you need to decide on is a power inverter and a battery. The inverter converts the DC output of the solar panels into AC power. You can have a single inverter receiving all the power from all the panels or have individual inverters per panel and combine the output at an AC panel.

The first option is better, but issues such as your space and the location of the panels are worth considering. Having a battery is a good practice as you can charge it during the day when the sun is up. Then, you can use the energy stored in the battery to recharge your car at night.

To finish setting up your solar charging system, you will need metal racks to mount your solar panels on the roof. Other considerations include the size of the cables and their length. You should choose a cable that offers a minimum voltage drop. This will help minimize losses between the panels and the inverter.

4. Your EV Charger

The final consideration is the type of EV charger to use. There are three levels of EV chargers: 1,2, and 3, but only the first two are suitable for home charging. Level 1 is portable, and you can plug it into the standard 10A power outlet. However, they require longer charging time and have lower efficiency, leaving you with level 2 chargers.

Level 2 chargers are dedicated wall-mounted chargers with an average rating of 7.4kW. As such, they can deliver the required charge for a 40-mile drive in less than two hours. For a 64kWh battery, charging would take 8 to 10 hours when using level 2 chargers, while using level 1 chargers would take 36 to 48 hours.

Final Thoughts

By owning an EV, you not only help save the world but also your finances. You can also get more out of your electric vehicle by using solar energy to charge it.

In addition, you will benefit from IRA tax credits that will quickly offset the initial installation costs. If you find setting up your home solar charging system too much of a hassle, reach out to an experienced solar energy firm and let them help you.